In recent years, trans-catheter aortic valve replacement (TAVR) has become increasingly used for the treatment of aortic stenosis. In TRVR, a surgical valve (prosthetic valve) is delivered via a catheter to the heart. During TAVR, transesophageal ultrasound (3D Transesophageal Echo: 3D-TEE) imaging is often performed to evaluate the reverse blood flow in a region of interest (a space between the aorta and the prosthetic valve) while the region is being observed by using an angiography apparatus, i.e., one example of the X-ray image diagnosis apparatus. In the transesophageal ultrasound (3D-TEE) imaging, a probe is inserted through the nose or the mouth to perform echocardiography in a subject's body (esophagus).
There has been proposed a technology, in which a transesophageal ultrasound (3D-TEE) image is read and displayed in fusion with an angiography image in real time.
Note that the trans-catheter aortic valve replacement may be sometimes called “trans-catheter aortic valve implantation (TAVI)”. Examples of the prosthetic valve include mechanical valves made of carbon resin or the like and bioprosthetic valves obtained by processing biological material such as animal tissue.